subnode.cpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25// Portions of code courtesy of Clifford Click 26 27// Optimization - Graph Style 28 29#include "incls/_precompiled.incl" 30#include "incls/_subnode.cpp.incl" 31#include "math.h" 32 33//============================================================================= 34//------------------------------Identity--------------------------------------- 35// If right input is a constant 0, return the left input. 36Node *SubNode::Identity( PhaseTransform *phase ) { 37 assert(in(1) != this, "Must already have called Value"); 38 assert(in(2) != this, "Must already have called Value"); 39 40 // Remove double negation 41 const Type *zero = add_id(); 42 if( phase->type( in(1) )->higher_equal( zero ) && 43 in(2)->Opcode() == Opcode() && 44 phase->type( in(2)->in(1) )->higher_equal( zero ) ) { 45 return in(2)->in(2); 46 } 47 48 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y 49 if( in(1)->Opcode() == Op_AddI ) { 50 if( phase->eqv(in(1)->in(2),in(2)) ) 51 return in(1)->in(1); 52 if (phase->eqv(in(1)->in(1),in(2))) 53 return in(1)->in(2); 54 55 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying 56 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes 57 // are originally used, although the optimizer sometimes jiggers things). 58 // This folding through an O2 removes a loop-exit use of a loop-varying 59 // value and generally lowers register pressure in and around the loop. 60 if( in(1)->in(2)->Opcode() == Op_Opaque2 && 61 phase->eqv(in(1)->in(2)->in(1),in(2)) ) 62 return in(1)->in(1); 63 } 64 65 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this; 66} 67 68//------------------------------Value------------------------------------------ 69// A subtract node differences it's two inputs. 70const Type *SubNode::Value( PhaseTransform *phase ) const { 71 const Node* in1 = in(1); 72 const Node* in2 = in(2); 73 // Either input is TOP ==> the result is TOP 74 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 75 if( t1 == Type::TOP ) return Type::TOP; 76 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 77 if( t2 == Type::TOP ) return Type::TOP; 78 79 // Not correct for SubFnode and AddFNode (must check for infinity) 80 // Equal? Subtract is zero 81 if (phase->eqv_uncast(in1, in2)) return add_id(); 82 83 // Either input is BOTTOM ==> the result is the local BOTTOM 84 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) 85 return bottom_type(); 86 87 return sub(t1,t2); // Local flavor of type subtraction 88 89} 90 91//============================================================================= 92 93//------------------------------Helper function-------------------------------- 94static bool ok_to_convert(Node* inc, Node* iv) { 95 // Do not collapse (x+c0)-y if "+" is a loop increment, because the 96 // "-" is loop invariant and collapsing extends the live-range of "x" 97 // to overlap with the "+", forcing another register to be used in 98 // the loop. 99 // This test will be clearer with '&&' (apply DeMorgan's rule) 100 // but I like the early cutouts that happen here. 101 const PhiNode *phi; 102 if( ( !inc->in(1)->is_Phi() || 103 !(phi=inc->in(1)->as_Phi()) || 104 phi->is_copy() || 105 !phi->region()->is_CountedLoop() || 106 inc != phi->region()->as_CountedLoop()->incr() ) 107 && 108 // Do not collapse (x+c0)-iv if "iv" is a loop induction variable, 109 // because "x" maybe invariant. 110 ( !iv->is_loop_iv() ) 111 ) { 112 return true; 113 } else { 114 return false; 115 } 116} 117//------------------------------Ideal------------------------------------------ 118Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){ 119 Node *in1 = in(1); 120 Node *in2 = in(2); 121 uint op1 = in1->Opcode(); 122 uint op2 = in2->Opcode(); 123 124#ifdef ASSERT 125 // Check for dead loop 126 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) || 127 ( op1 == Op_AddI || op1 == Op_SubI ) && 128 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) || 129 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) 130 assert(false, "dead loop in SubINode::Ideal"); 131#endif 132 133 const Type *t2 = phase->type( in2 ); 134 if( t2 == Type::TOP ) return NULL; 135 // Convert "x-c0" into "x+ -c0". 136 if( t2->base() == Type::Int ){ // Might be bottom or top... 137 const TypeInt *i = t2->is_int(); 138 if( i->is_con() ) 139 return new (phase->C, 3) AddINode(in1, phase->intcon(-i->get_con())); 140 } 141 142 // Convert "(x+c0) - y" into (x-y) + c0" 143 // Do not collapse (x+c0)-y if "+" is a loop increment or 144 // if "y" is a loop induction variable. 145 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) { 146 const Type *tadd = phase->type( in1->in(2) ); 147 if( tadd->singleton() && tadd != Type::TOP ) { 148 Node *sub2 = phase->transform( new (phase->C, 3) SubINode( in1->in(1), in2 )); 149 return new (phase->C, 3) AddINode( sub2, in1->in(2) ); 150 } 151 } 152 153 154 // Convert "x - (y+c0)" into "(x-y) - c0" 155 // Need the same check as in above optimization but reversed. 156 if (op2 == Op_AddI && ok_to_convert(in2, in1)) { 157 Node* in21 = in2->in(1); 158 Node* in22 = in2->in(2); 159 const TypeInt* tcon = phase->type(in22)->isa_int(); 160 if (tcon != NULL && tcon->is_con()) { 161 Node* sub2 = phase->transform( new (phase->C, 3) SubINode(in1, in21) ); 162 Node* neg_c0 = phase->intcon(- tcon->get_con()); 163 return new (phase->C, 3) AddINode(sub2, neg_c0); 164 } 165 } 166 167 const Type *t1 = phase->type( in1 ); 168 if( t1 == Type::TOP ) return NULL; 169 170#ifdef ASSERT 171 // Check for dead loop 172 if( ( op2 == Op_AddI || op2 == Op_SubI ) && 173 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) || 174 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) ) 175 assert(false, "dead loop in SubINode::Ideal"); 176#endif 177 178 // Convert "x - (x+y)" into "-y" 179 if( op2 == Op_AddI && 180 phase->eqv( in1, in2->in(1) ) ) 181 return new (phase->C, 3) SubINode( phase->intcon(0),in2->in(2)); 182 // Convert "(x-y) - x" into "-y" 183 if( op1 == Op_SubI && 184 phase->eqv( in1->in(1), in2 ) ) 185 return new (phase->C, 3) SubINode( phase->intcon(0),in1->in(2)); 186 // Convert "x - (y+x)" into "-y" 187 if( op2 == Op_AddI && 188 phase->eqv( in1, in2->in(2) ) ) 189 return new (phase->C, 3) SubINode( phase->intcon(0),in2->in(1)); 190 191 // Convert "0 - (x-y)" into "y-x" 192 if( t1 == TypeInt::ZERO && op2 == Op_SubI ) 193 return new (phase->C, 3) SubINode( in2->in(2), in2->in(1) ); 194 195 // Convert "0 - (x+con)" into "-con-x" 196 jint con; 197 if( t1 == TypeInt::ZERO && op2 == Op_AddI && 198 (con = in2->in(2)->find_int_con(0)) != 0 ) 199 return new (phase->C, 3) SubINode( phase->intcon(-con), in2->in(1) ); 200 201 // Convert "(X+A) - (X+B)" into "A - B" 202 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) ) 203 return new (phase->C, 3) SubINode( in1->in(2), in2->in(2) ); 204 205 // Convert "(A+X) - (B+X)" into "A - B" 206 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) ) 207 return new (phase->C, 3) SubINode( in1->in(1), in2->in(1) ); 208 209 // Convert "(A+X) - (X+B)" into "A - B" 210 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) ) 211 return new (phase->C, 3) SubINode( in1->in(1), in2->in(2) ); 212 213 // Convert "(X+A) - (B+X)" into "A - B" 214 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) ) 215 return new (phase->C, 3) SubINode( in1->in(2), in2->in(1) ); 216 217 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally 218 // nicer to optimize than subtract. 219 if( op2 == Op_SubI && in2->outcnt() == 1) { 220 Node *add1 = phase->transform( new (phase->C, 3) AddINode( in1, in2->in(2) ) ); 221 return new (phase->C, 3) SubINode( add1, in2->in(1) ); 222 } 223 224 return NULL; 225} 226 227//------------------------------sub-------------------------------------------- 228// A subtract node differences it's two inputs. 229const Type *SubINode::sub( const Type *t1, const Type *t2 ) const { 230 const TypeInt *r0 = t1->is_int(); // Handy access 231 const TypeInt *r1 = t2->is_int(); 232 int32 lo = r0->_lo - r1->_hi; 233 int32 hi = r0->_hi - r1->_lo; 234 235 // We next check for 32-bit overflow. 236 // If that happens, we just assume all integers are possible. 237 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 238 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 239 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 240 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 241 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 242 else // Overflow; assume all integers 243 return TypeInt::INT; 244} 245 246//============================================================================= 247//------------------------------Ideal------------------------------------------ 248Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 249 Node *in1 = in(1); 250 Node *in2 = in(2); 251 uint op1 = in1->Opcode(); 252 uint op2 = in2->Opcode(); 253 254#ifdef ASSERT 255 // Check for dead loop 256 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) || 257 ( op1 == Op_AddL || op1 == Op_SubL ) && 258 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) || 259 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) 260 assert(false, "dead loop in SubLNode::Ideal"); 261#endif 262 263 if( phase->type( in2 ) == Type::TOP ) return NULL; 264 const TypeLong *i = phase->type( in2 )->isa_long(); 265 // Convert "x-c0" into "x+ -c0". 266 if( i && // Might be bottom or top... 267 i->is_con() ) 268 return new (phase->C, 3) AddLNode(in1, phase->longcon(-i->get_con())); 269 270 // Convert "(x+c0) - y" into (x-y) + c0" 271 // Do not collapse (x+c0)-y if "+" is a loop increment or 272 // if "y" is a loop induction variable. 273 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) { 274 Node *in11 = in1->in(1); 275 const Type *tadd = phase->type( in1->in(2) ); 276 if( tadd->singleton() && tadd != Type::TOP ) { 277 Node *sub2 = phase->transform( new (phase->C, 3) SubLNode( in11, in2 )); 278 return new (phase->C, 3) AddLNode( sub2, in1->in(2) ); 279 } 280 } 281 282 // Convert "x - (y+c0)" into "(x-y) - c0" 283 // Need the same check as in above optimization but reversed. 284 if (op2 == Op_AddL && ok_to_convert(in2, in1)) { 285 Node* in21 = in2->in(1); 286 Node* in22 = in2->in(2); 287 const TypeLong* tcon = phase->type(in22)->isa_long(); 288 if (tcon != NULL && tcon->is_con()) { 289 Node* sub2 = phase->transform( new (phase->C, 3) SubLNode(in1, in21) ); 290 Node* neg_c0 = phase->longcon(- tcon->get_con()); 291 return new (phase->C, 3) AddLNode(sub2, neg_c0); 292 } 293 } 294 295 const Type *t1 = phase->type( in1 ); 296 if( t1 == Type::TOP ) return NULL; 297 298#ifdef ASSERT 299 // Check for dead loop 300 if( ( op2 == Op_AddL || op2 == Op_SubL ) && 301 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) || 302 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) ) 303 assert(false, "dead loop in SubLNode::Ideal"); 304#endif 305 306 // Convert "x - (x+y)" into "-y" 307 if( op2 == Op_AddL && 308 phase->eqv( in1, in2->in(1) ) ) 309 return new (phase->C, 3) SubLNode( phase->makecon(TypeLong::ZERO), in2->in(2)); 310 // Convert "x - (y+x)" into "-y" 311 if( op2 == Op_AddL && 312 phase->eqv( in1, in2->in(2) ) ) 313 return new (phase->C, 3) SubLNode( phase->makecon(TypeLong::ZERO),in2->in(1)); 314 315 // Convert "0 - (x-y)" into "y-x" 316 if( phase->type( in1 ) == TypeLong::ZERO && op2 == Op_SubL ) 317 return new (phase->C, 3) SubLNode( in2->in(2), in2->in(1) ); 318 319 // Convert "(X+A) - (X+B)" into "A - B" 320 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) ) 321 return new (phase->C, 3) SubLNode( in1->in(2), in2->in(2) ); 322 323 // Convert "(A+X) - (B+X)" into "A - B" 324 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) ) 325 return new (phase->C, 3) SubLNode( in1->in(1), in2->in(1) ); 326 327 // Convert "A-(B-C)" into (A+C)-B" 328 if( op2 == Op_SubL && in2->outcnt() == 1) { 329 Node *add1 = phase->transform( new (phase->C, 3) AddLNode( in1, in2->in(2) ) ); 330 return new (phase->C, 3) SubLNode( add1, in2->in(1) ); 331 } 332 333 return NULL; 334} 335 336//------------------------------sub-------------------------------------------- 337// A subtract node differences it's two inputs. 338const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const { 339 const TypeLong *r0 = t1->is_long(); // Handy access 340 const TypeLong *r1 = t2->is_long(); 341 jlong lo = r0->_lo - r1->_hi; 342 jlong hi = r0->_hi - r1->_lo; 343 344 // We next check for 32-bit overflow. 345 // If that happens, we just assume all integers are possible. 346 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 347 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 348 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 349 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 350 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 351 else // Overflow; assume all integers 352 return TypeLong::LONG; 353} 354 355//============================================================================= 356//------------------------------Value------------------------------------------ 357// A subtract node differences its two inputs. 358const Type *SubFPNode::Value( PhaseTransform *phase ) const { 359 const Node* in1 = in(1); 360 const Node* in2 = in(2); 361 // Either input is TOP ==> the result is TOP 362 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 363 if( t1 == Type::TOP ) return Type::TOP; 364 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 365 if( t2 == Type::TOP ) return Type::TOP; 366 367 // if both operands are infinity of same sign, the result is NaN; do 368 // not replace with zero 369 if( (t1->is_finite() && t2->is_finite()) ) { 370 if( phase->eqv(in1, in2) ) return add_id(); 371 } 372 373 // Either input is BOTTOM ==> the result is the local BOTTOM 374 const Type *bot = bottom_type(); 375 if( (t1 == bot) || (t2 == bot) || 376 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 377 return bot; 378 379 return sub(t1,t2); // Local flavor of type subtraction 380} 381 382 383//============================================================================= 384//------------------------------Ideal------------------------------------------ 385Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 386 const Type *t2 = phase->type( in(2) ); 387 // Convert "x-c0" into "x+ -c0". 388 if( t2->base() == Type::FloatCon ) { // Might be bottom or top... 389 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) ); 390 } 391 392 // Not associative because of boundary conditions (infinity) 393 if( IdealizedNumerics && !phase->C->method()->is_strict() ) { 394 // Convert "x - (x+y)" into "-y" 395 if( in(2)->is_Add() && 396 phase->eqv(in(1),in(2)->in(1) ) ) 397 return new (phase->C, 3) SubFNode( phase->makecon(TypeF::ZERO),in(2)->in(2)); 398 } 399 400 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes 401 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0. 402 //if( phase->type(in(1)) == TypeF::ZERO ) 403 //return new (phase->C, 2) NegFNode(in(2)); 404 405 return NULL; 406} 407 408//------------------------------sub-------------------------------------------- 409// A subtract node differences its two inputs. 410const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const { 411 // no folding if one of operands is infinity or NaN, do not do constant folding 412 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) { 413 return TypeF::make( t1->getf() - t2->getf() ); 414 } 415 else if( g_isnan(t1->getf()) ) { 416 return t1; 417 } 418 else if( g_isnan(t2->getf()) ) { 419 return t2; 420 } 421 else { 422 return Type::FLOAT; 423 } 424} 425 426//============================================================================= 427//------------------------------Ideal------------------------------------------ 428Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 429 const Type *t2 = phase->type( in(2) ); 430 // Convert "x-c0" into "x+ -c0". 431 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top... 432 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) ); 433 } 434 435 // Not associative because of boundary conditions (infinity) 436 if( IdealizedNumerics && !phase->C->method()->is_strict() ) { 437 // Convert "x - (x+y)" into "-y" 438 if( in(2)->is_Add() && 439 phase->eqv(in(1),in(2)->in(1) ) ) 440 return new (phase->C, 3) SubDNode( phase->makecon(TypeD::ZERO),in(2)->in(2)); 441 } 442 443 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes 444 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0. 445 //if( phase->type(in(1)) == TypeD::ZERO ) 446 //return new (phase->C, 2) NegDNode(in(2)); 447 448 return NULL; 449} 450 451//------------------------------sub-------------------------------------------- 452// A subtract node differences its two inputs. 453const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const { 454 // no folding if one of operands is infinity or NaN, do not do constant folding 455 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) { 456 return TypeD::make( t1->getd() - t2->getd() ); 457 } 458 else if( g_isnan(t1->getd()) ) { 459 return t1; 460 } 461 else if( g_isnan(t2->getd()) ) { 462 return t2; 463 } 464 else { 465 return Type::DOUBLE; 466 } 467} 468 469//============================================================================= 470//------------------------------Idealize--------------------------------------- 471// Unlike SubNodes, compare must still flatten return value to the 472// range -1, 0, 1. 473// And optimizations like those for (X + Y) - X fail if overflow happens. 474Node *CmpNode::Identity( PhaseTransform *phase ) { 475 return this; 476} 477 478//============================================================================= 479//------------------------------cmp-------------------------------------------- 480// Simplify a CmpI (compare 2 integers) node, based on local information. 481// If both inputs are constants, compare them. 482const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const { 483 const TypeInt *r0 = t1->is_int(); // Handy access 484 const TypeInt *r1 = t2->is_int(); 485 486 if( r0->_hi < r1->_lo ) // Range is always low? 487 return TypeInt::CC_LT; 488 else if( r0->_lo > r1->_hi ) // Range is always high? 489 return TypeInt::CC_GT; 490 491 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 492 assert(r0->get_con() == r1->get_con(), "must be equal"); 493 return TypeInt::CC_EQ; // Equal results. 494 } else if( r0->_hi == r1->_lo ) // Range is never high? 495 return TypeInt::CC_LE; 496 else if( r0->_lo == r1->_hi ) // Range is never low? 497 return TypeInt::CC_GE; 498 return TypeInt::CC; // else use worst case results 499} 500 501// Simplify a CmpU (compare 2 integers) node, based on local information. 502// If both inputs are constants, compare them. 503const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const { 504 assert(!t1->isa_ptr(), "obsolete usage of CmpU"); 505 506 // comparing two unsigned ints 507 const TypeInt *r0 = t1->is_int(); // Handy access 508 const TypeInt *r1 = t2->is_int(); 509 510 // Current installed version 511 // Compare ranges for non-overlap 512 juint lo0 = r0->_lo; 513 juint hi0 = r0->_hi; 514 juint lo1 = r1->_lo; 515 juint hi1 = r1->_hi; 516 517 // If either one has both negative and positive values, 518 // it therefore contains both 0 and -1, and since [0..-1] is the 519 // full unsigned range, the type must act as an unsigned bottom. 520 bool bot0 = ((jint)(lo0 ^ hi0) < 0); 521 bool bot1 = ((jint)(lo1 ^ hi1) < 0); 522 523 if (bot0 || bot1) { 524 // All unsigned values are LE -1 and GE 0. 525 if (lo0 == 0 && hi0 == 0) { 526 return TypeInt::CC_LE; // 0 <= bot 527 } else if (lo1 == 0 && hi1 == 0) { 528 return TypeInt::CC_GE; // bot >= 0 529 } 530 } else { 531 // We can use ranges of the form [lo..hi] if signs are the same. 532 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 533 // results are reversed, '-' > '+' for unsigned compare 534 if (hi0 < lo1) { 535 return TypeInt::CC_LT; // smaller 536 } else if (lo0 > hi1) { 537 return TypeInt::CC_GT; // greater 538 } else if (hi0 == lo1 && lo0 == hi1) { 539 return TypeInt::CC_EQ; // Equal results 540 } else if (lo0 >= hi1) { 541 return TypeInt::CC_GE; 542 } else if (hi0 <= lo1) { 543 // Check for special case in Hashtable::get. (See below.) 544 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && 545 in(1)->Opcode() == Op_ModI && 546 in(1)->in(2) == in(2) ) 547 return TypeInt::CC_LT; 548 return TypeInt::CC_LE; 549 } 550 } 551 // Check for special case in Hashtable::get - the hash index is 552 // mod'ed to the table size so the following range check is useless. 553 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have 554 // to be positive. 555 // (This is a gross hack, since the sub method never 556 // looks at the structure of the node in any other case.) 557 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && 558 in(1)->Opcode() == Op_ModI && 559 in(1)->in(2)->uncast() == in(2)->uncast()) 560 return TypeInt::CC_LT; 561 return TypeInt::CC; // else use worst case results 562} 563 564//------------------------------Idealize--------------------------------------- 565Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) { 566 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) { 567 switch (in(1)->Opcode()) { 568 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL 569 return new (phase->C, 3) CmpLNode(in(1)->in(1),in(1)->in(2)); 570 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF 571 return new (phase->C, 3) CmpFNode(in(1)->in(1),in(1)->in(2)); 572 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD 573 return new (phase->C, 3) CmpDNode(in(1)->in(1),in(1)->in(2)); 574 //case Op_SubI: 575 // If (x - y) cannot overflow, then ((x - y) <?> 0) 576 // can be turned into (x <?> y). 577 // This is handled (with more general cases) by Ideal_sub_algebra. 578 } 579 } 580 return NULL; // No change 581} 582 583 584//============================================================================= 585// Simplify a CmpL (compare 2 longs ) node, based on local information. 586// If both inputs are constants, compare them. 587const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const { 588 const TypeLong *r0 = t1->is_long(); // Handy access 589 const TypeLong *r1 = t2->is_long(); 590 591 if( r0->_hi < r1->_lo ) // Range is always low? 592 return TypeInt::CC_LT; 593 else if( r0->_lo > r1->_hi ) // Range is always high? 594 return TypeInt::CC_GT; 595 596 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 597 assert(r0->get_con() == r1->get_con(), "must be equal"); 598 return TypeInt::CC_EQ; // Equal results. 599 } else if( r0->_hi == r1->_lo ) // Range is never high? 600 return TypeInt::CC_LE; 601 else if( r0->_lo == r1->_hi ) // Range is never low? 602 return TypeInt::CC_GE; 603 return TypeInt::CC; // else use worst case results 604} 605 606//============================================================================= 607//------------------------------sub-------------------------------------------- 608// Simplify an CmpP (compare 2 pointers) node, based on local information. 609// If both inputs are constants, compare them. 610const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const { 611 const TypePtr *r0 = t1->is_ptr(); // Handy access 612 const TypePtr *r1 = t2->is_ptr(); 613 614 // Undefined inputs makes for an undefined result 615 if( TypePtr::above_centerline(r0->_ptr) || 616 TypePtr::above_centerline(r1->_ptr) ) 617 return Type::TOP; 618 619 if (r0 == r1 && r0->singleton()) { 620 // Equal pointer constants (klasses, nulls, etc.) 621 return TypeInt::CC_EQ; 622 } 623 624 // See if it is 2 unrelated classes. 625 const TypeOopPtr* p0 = r0->isa_oopptr(); 626 const TypeOopPtr* p1 = r1->isa_oopptr(); 627 if (p0 && p1) { 628 Node* in1 = in(1)->uncast(); 629 Node* in2 = in(2)->uncast(); 630 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL); 631 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL); 632 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) { 633 return TypeInt::CC_GT; // different pointers 634 } 635 ciKlass* klass0 = p0->klass(); 636 bool xklass0 = p0->klass_is_exact(); 637 ciKlass* klass1 = p1->klass(); 638 bool xklass1 = p1->klass_is_exact(); 639 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0); 640 if (klass0 && klass1 && 641 kps != 1 && // both or neither are klass pointers 642 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces 643 klass1->is_loaded() && !klass1->is_interface() && 644 (!klass0->is_obj_array_klass() || 645 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) && 646 (!klass1->is_obj_array_klass() || 647 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) { 648 bool unrelated_classes = false; 649 // See if neither subclasses the other, or if the class on top 650 // is precise. In either of these cases, the compare is known 651 // to fail if at least one of the pointers is provably not null. 652 if (klass0->equals(klass1) || // if types are unequal but klasses are 653 !klass0->is_java_klass() || // types not part of Java language? 654 !klass1->is_java_klass()) { // types not part of Java language? 655 // Do nothing; we know nothing for imprecise types 656 } else if (klass0->is_subtype_of(klass1)) { 657 // If klass1's type is PRECISE, then classes are unrelated. 658 unrelated_classes = xklass1; 659 } else if (klass1->is_subtype_of(klass0)) { 660 // If klass0's type is PRECISE, then classes are unrelated. 661 unrelated_classes = xklass0; 662 } else { // Neither subtypes the other 663 unrelated_classes = true; 664 } 665 if (unrelated_classes) { 666 // The oops classes are known to be unrelated. If the joined PTRs of 667 // two oops is not Null and not Bottom, then we are sure that one 668 // of the two oops is non-null, and the comparison will always fail. 669 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 670 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 671 return TypeInt::CC_GT; 672 } 673 } 674 } 675 } 676 677 // Known constants can be compared exactly 678 // Null can be distinguished from any NotNull pointers 679 // Unknown inputs makes an unknown result 680 if( r0->singleton() ) { 681 intptr_t bits0 = r0->get_con(); 682 if( r1->singleton() ) 683 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 684 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 685 } else if( r1->singleton() ) { 686 intptr_t bits1 = r1->get_con(); 687 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 688 } else 689 return TypeInt::CC; 690} 691 692//------------------------------Ideal------------------------------------------ 693// Check for the case of comparing an unknown klass loaded from the primary 694// super-type array vs a known klass with no subtypes. This amounts to 695// checking to see an unknown klass subtypes a known klass with no subtypes; 696// this only happens on an exact match. We can shorten this test by 1 load. 697Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 698 // Constant pointer on right? 699 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr(); 700 if (t2 == NULL || !t2->klass_is_exact()) 701 return NULL; 702 // Get the constant klass we are comparing to. 703 ciKlass* superklass = t2->klass(); 704 705 // Now check for LoadKlass on left. 706 Node* ldk1 = in(1); 707 if (ldk1->is_DecodeN()) { 708 ldk1 = ldk1->in(1); 709 if (ldk1->Opcode() != Op_LoadNKlass ) 710 return NULL; 711 } else if (ldk1->Opcode() != Op_LoadKlass ) 712 return NULL; 713 // Take apart the address of the LoadKlass: 714 Node* adr1 = ldk1->in(MemNode::Address); 715 intptr_t con2 = 0; 716 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2); 717 if (ldk2 == NULL) 718 return NULL; 719 if (con2 == oopDesc::klass_offset_in_bytes()) { 720 // We are inspecting an object's concrete class. 721 // Short-circuit the check if the query is abstract. 722 if (superklass->is_interface() || 723 superklass->is_abstract()) { 724 // Make it come out always false: 725 this->set_req(2, phase->makecon(TypePtr::NULL_PTR)); 726 return this; 727 } 728 } 729 730 // Check for a LoadKlass from primary supertype array. 731 // Any nested loadklass from loadklass+con must be from the p.s. array. 732 if (ldk2->is_DecodeN()) { 733 // Keep ldk2 as DecodeN since it could be used in CmpP below. 734 if (ldk2->in(1)->Opcode() != Op_LoadNKlass ) 735 return NULL; 736 } else if (ldk2->Opcode() != Op_LoadKlass) 737 return NULL; 738 739 // Verify that we understand the situation 740 if (con2 != (intptr_t) superklass->super_check_offset()) 741 return NULL; // Might be element-klass loading from array klass 742 743 // If 'superklass' has no subklasses and is not an interface, then we are 744 // assured that the only input which will pass the type check is 745 // 'superklass' itself. 746 // 747 // We could be more liberal here, and allow the optimization on interfaces 748 // which have a single implementor. This would require us to increase the 749 // expressiveness of the add_dependency() mechanism. 750 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now. 751 752 // Object arrays must have their base element have no subtypes 753 while (superklass->is_obj_array_klass()) { 754 ciType* elem = superklass->as_obj_array_klass()->element_type(); 755 superklass = elem->as_klass(); 756 } 757 if (superklass->is_instance_klass()) { 758 ciInstanceKlass* ik = superklass->as_instance_klass(); 759 if (ik->has_subklass() || ik->is_interface()) return NULL; 760 // Add a dependency if there is a chance that a subclass will be added later. 761 if (!ik->is_final()) { 762 phase->C->dependencies()->assert_leaf_type(ik); 763 } 764 } 765 766 // Bypass the dependent load, and compare directly 767 this->set_req(1,ldk2); 768 769 return this; 770} 771 772//============================================================================= 773//------------------------------sub-------------------------------------------- 774// Simplify an CmpN (compare 2 pointers) node, based on local information. 775// If both inputs are constants, compare them. 776const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const { 777 const TypePtr *r0 = t1->make_ptr(); // Handy access 778 const TypePtr *r1 = t2->make_ptr(); 779 780 // Undefined inputs makes for an undefined result 781 if( TypePtr::above_centerline(r0->_ptr) || 782 TypePtr::above_centerline(r1->_ptr) ) 783 return Type::TOP; 784 785 if (r0 == r1 && r0->singleton()) { 786 // Equal pointer constants (klasses, nulls, etc.) 787 return TypeInt::CC_EQ; 788 } 789 790 // See if it is 2 unrelated classes. 791 const TypeOopPtr* p0 = r0->isa_oopptr(); 792 const TypeOopPtr* p1 = r1->isa_oopptr(); 793 if (p0 && p1) { 794 ciKlass* klass0 = p0->klass(); 795 bool xklass0 = p0->klass_is_exact(); 796 ciKlass* klass1 = p1->klass(); 797 bool xklass1 = p1->klass_is_exact(); 798 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0); 799 if (klass0 && klass1 && 800 kps != 1 && // both or neither are klass pointers 801 !klass0->is_interface() && // do not trust interfaces 802 !klass1->is_interface()) { 803 bool unrelated_classes = false; 804 // See if neither subclasses the other, or if the class on top 805 // is precise. In either of these cases, the compare is known 806 // to fail if at least one of the pointers is provably not null. 807 if (klass0->equals(klass1) || // if types are unequal but klasses are 808 !klass0->is_java_klass() || // types not part of Java language? 809 !klass1->is_java_klass()) { // types not part of Java language? 810 // Do nothing; we know nothing for imprecise types 811 } else if (klass0->is_subtype_of(klass1)) { 812 // If klass1's type is PRECISE, then classes are unrelated. 813 unrelated_classes = xklass1; 814 } else if (klass1->is_subtype_of(klass0)) { 815 // If klass0's type is PRECISE, then classes are unrelated. 816 unrelated_classes = xklass0; 817 } else { // Neither subtypes the other 818 unrelated_classes = true; 819 } 820 if (unrelated_classes) { 821 // The oops classes are known to be unrelated. If the joined PTRs of 822 // two oops is not Null and not Bottom, then we are sure that one 823 // of the two oops is non-null, and the comparison will always fail. 824 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 825 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 826 return TypeInt::CC_GT; 827 } 828 } 829 } 830 } 831 832 // Known constants can be compared exactly 833 // Null can be distinguished from any NotNull pointers 834 // Unknown inputs makes an unknown result 835 if( r0->singleton() ) { 836 intptr_t bits0 = r0->get_con(); 837 if( r1->singleton() ) 838 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 839 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 840 } else if( r1->singleton() ) { 841 intptr_t bits1 = r1->get_con(); 842 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 843 } else 844 return TypeInt::CC; 845} 846 847//------------------------------Ideal------------------------------------------ 848Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 849 return NULL; 850} 851 852//============================================================================= 853//------------------------------Value------------------------------------------ 854// Simplify an CmpF (compare 2 floats ) node, based on local information. 855// If both inputs are constants, compare them. 856const Type *CmpFNode::Value( PhaseTransform *phase ) const { 857 const Node* in1 = in(1); 858 const Node* in2 = in(2); 859 // Either input is TOP ==> the result is TOP 860 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 861 if( t1 == Type::TOP ) return Type::TOP; 862 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 863 if( t2 == Type::TOP ) return Type::TOP; 864 865 // Not constants? Don't know squat - even if they are the same 866 // value! If they are NaN's they compare to LT instead of EQ. 867 const TypeF *tf1 = t1->isa_float_constant(); 868 const TypeF *tf2 = t2->isa_float_constant(); 869 if( !tf1 || !tf2 ) return TypeInt::CC; 870 871 // This implements the Java bytecode fcmpl, so unordered returns -1. 872 if( tf1->is_nan() || tf2->is_nan() ) 873 return TypeInt::CC_LT; 874 875 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT; 876 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT; 877 assert( tf1->_f == tf2->_f, "do not understand FP behavior" ); 878 return TypeInt::CC_EQ; 879} 880 881 882//============================================================================= 883//------------------------------Value------------------------------------------ 884// Simplify an CmpD (compare 2 doubles ) node, based on local information. 885// If both inputs are constants, compare them. 886const Type *CmpDNode::Value( PhaseTransform *phase ) const { 887 const Node* in1 = in(1); 888 const Node* in2 = in(2); 889 // Either input is TOP ==> the result is TOP 890 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 891 if( t1 == Type::TOP ) return Type::TOP; 892 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 893 if( t2 == Type::TOP ) return Type::TOP; 894 895 // Not constants? Don't know squat - even if they are the same 896 // value! If they are NaN's they compare to LT instead of EQ. 897 const TypeD *td1 = t1->isa_double_constant(); 898 const TypeD *td2 = t2->isa_double_constant(); 899 if( !td1 || !td2 ) return TypeInt::CC; 900 901 // This implements the Java bytecode dcmpl, so unordered returns -1. 902 if( td1->is_nan() || td2->is_nan() ) 903 return TypeInt::CC_LT; 904 905 if( td1->_d < td2->_d ) return TypeInt::CC_LT; 906 if( td1->_d > td2->_d ) return TypeInt::CC_GT; 907 assert( td1->_d == td2->_d, "do not understand FP behavior" ); 908 return TypeInt::CC_EQ; 909} 910 911//------------------------------Ideal------------------------------------------ 912Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 913 // Check if we can change this to a CmpF and remove a ConvD2F operation. 914 // Change (CMPD (F2D (float)) (ConD value)) 915 // To (CMPF (float) (ConF value)) 916 // Valid when 'value' does not lose precision as a float. 917 // Benefits: eliminates conversion, does not require 24-bit mode 918 919 // NaNs prevent commuting operands. This transform works regardless of the 920 // order of ConD and ConvF2D inputs by preserving the original order. 921 int idx_f2d = 1; // ConvF2D on left side? 922 if( in(idx_f2d)->Opcode() != Op_ConvF2D ) 923 idx_f2d = 2; // No, swap to check for reversed args 924 int idx_con = 3-idx_f2d; // Check for the constant on other input 925 926 if( ConvertCmpD2CmpF && 927 in(idx_f2d)->Opcode() == Op_ConvF2D && 928 in(idx_con)->Opcode() == Op_ConD ) { 929 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant(); 930 double t2_value_as_double = t2->_d; 931 float t2_value_as_float = (float)t2_value_as_double; 932 if( t2_value_as_double == (double)t2_value_as_float ) { 933 // Test value can be represented as a float 934 // Eliminate the conversion to double and create new comparison 935 Node *new_in1 = in(idx_f2d)->in(1); 936 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) ); 937 if( idx_f2d != 1 ) { // Must flip args to match original order 938 Node *tmp = new_in1; 939 new_in1 = new_in2; 940 new_in2 = tmp; 941 } 942 CmpFNode *new_cmp = (Opcode() == Op_CmpD3) 943 ? new (phase->C, 3) CmpF3Node( new_in1, new_in2 ) 944 : new (phase->C, 3) CmpFNode ( new_in1, new_in2 ) ; 945 return new_cmp; // Changed to CmpFNode 946 } 947 // Testing value required the precision of a double 948 } 949 return NULL; // No change 950} 951 952 953//============================================================================= 954//------------------------------cc2logical------------------------------------- 955// Convert a condition code type to a logical type 956const Type *BoolTest::cc2logical( const Type *CC ) const { 957 if( CC == Type::TOP ) return Type::TOP; 958 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse 959 const TypeInt *ti = CC->is_int(); 960 if( ti->is_con() ) { // Only 1 kind of condition codes set? 961 // Match low order 2 bits 962 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0; 963 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result 964 return TypeInt::make(tmp); // Boolean result 965 } 966 967 if( CC == TypeInt::CC_GE ) { 968 if( _test == ge ) return TypeInt::ONE; 969 if( _test == lt ) return TypeInt::ZERO; 970 } 971 if( CC == TypeInt::CC_LE ) { 972 if( _test == le ) return TypeInt::ONE; 973 if( _test == gt ) return TypeInt::ZERO; 974 } 975 976 return TypeInt::BOOL; 977} 978 979//------------------------------dump_spec------------------------------------- 980// Print special per-node info 981#ifndef PRODUCT 982void BoolTest::dump_on(outputStream *st) const { 983 const char *msg[] = {"eq","gt","??","lt","ne","le","??","ge"}; 984 st->print(msg[_test]); 985} 986#endif 987 988//============================================================================= 989uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); } 990uint BoolNode::size_of() const { return sizeof(BoolNode); } 991 992//------------------------------operator==------------------------------------- 993uint BoolNode::cmp( const Node &n ) const { 994 const BoolNode *b = (const BoolNode *)&n; // Cast up 995 return (_test._test == b->_test._test); 996} 997 998//------------------------------clone_cmp-------------------------------------- 999// Clone a compare/bool tree 1000static Node *clone_cmp( Node *cmp, Node *cmp1, Node *cmp2, PhaseGVN *gvn, BoolTest::mask test ) { 1001 Node *ncmp = cmp->clone(); 1002 ncmp->set_req(1,cmp1); 1003 ncmp->set_req(2,cmp2); 1004 ncmp = gvn->transform( ncmp ); 1005 return new (gvn->C, 2) BoolNode( ncmp, test ); 1006} 1007 1008//-------------------------------make_predicate-------------------------------- 1009Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) { 1010 if (test_value->is_Con()) return test_value; 1011 if (test_value->is_Bool()) return test_value; 1012 Compile* C = phase->C; 1013 if (test_value->is_CMove() && 1014 test_value->in(CMoveNode::Condition)->is_Bool()) { 1015 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool(); 1016 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse)); 1017 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue)); 1018 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) { 1019 return bol; 1020 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) { 1021 return phase->transform( bol->negate(phase) ); 1022 } 1023 // Else fall through. The CMove gets in the way of the test. 1024 // It should be the case that make_predicate(bol->as_int_value()) == bol. 1025 } 1026 Node* cmp = new (C, 3) CmpINode(test_value, phase->intcon(0)); 1027 cmp = phase->transform(cmp); 1028 Node* bol = new (C, 2) BoolNode(cmp, BoolTest::ne); 1029 return phase->transform(bol); 1030} 1031 1032//--------------------------------as_int_value--------------------------------- 1033Node* BoolNode::as_int_value(PhaseGVN* phase) { 1034 // Inverse to make_predicate. The CMove probably boils down to a Conv2B. 1035 Node* cmov = CMoveNode::make(phase->C, NULL, this, 1036 phase->intcon(0), phase->intcon(1), 1037 TypeInt::BOOL); 1038 return phase->transform(cmov); 1039} 1040 1041//----------------------------------negate------------------------------------- 1042BoolNode* BoolNode::negate(PhaseGVN* phase) { 1043 Compile* C = phase->C; 1044 return new (C, 2) BoolNode(in(1), _test.negate()); 1045} 1046 1047 1048//------------------------------Ideal------------------------------------------ 1049Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1050 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)". 1051 // This moves the constant to the right. Helps value-numbering. 1052 Node *cmp = in(1); 1053 if( !cmp->is_Sub() ) return NULL; 1054 int cop = cmp->Opcode(); 1055 if( cop == Op_FastLock || cop == Op_FastUnlock ) return NULL; 1056 Node *cmp1 = cmp->in(1); 1057 Node *cmp2 = cmp->in(2); 1058 if( !cmp1 ) return NULL; 1059 1060 // Constant on left? 1061 Node *con = cmp1; 1062 uint op2 = cmp2->Opcode(); 1063 // Move constants to the right of compare's to canonicalize. 1064 // Do not muck with Opaque1 nodes, as this indicates a loop 1065 // guard that cannot change shape. 1066 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 && 1067 // Because of NaN's, CmpD and CmpF are not commutative 1068 cop != Op_CmpD && cop != Op_CmpF && 1069 // Protect against swapping inputs to a compare when it is used by a 1070 // counted loop exit, which requires maintaining the loop-limit as in(2) 1071 !is_counted_loop_exit_test() ) { 1072 // Ok, commute the constant to the right of the cmp node. 1073 // Clone the Node, getting a new Node of the same class 1074 cmp = cmp->clone(); 1075 // Swap inputs to the clone 1076 cmp->swap_edges(1, 2); 1077 cmp = phase->transform( cmp ); 1078 return new (phase->C, 2) BoolNode( cmp, _test.commute() ); 1079 } 1080 1081 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)". 1082 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the 1083 // test instead. 1084 int cmp1_op = cmp1->Opcode(); 1085 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int(); 1086 if (cmp2_type == NULL) return NULL; 1087 Node* j_xor = cmp1; 1088 if( cmp2_type == TypeInt::ZERO && 1089 cmp1_op == Op_XorI && 1090 j_xor->in(1) != j_xor && // An xor of itself is dead 1091 phase->type( j_xor->in(2) ) == TypeInt::ONE && 1092 (_test._test == BoolTest::eq || 1093 _test._test == BoolTest::ne) ) { 1094 Node *ncmp = phase->transform(new (phase->C, 3) CmpINode(j_xor->in(1),cmp2)); 1095 return new (phase->C, 2) BoolNode( ncmp, _test.negate() ); 1096 } 1097 1098 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)". 1099 // This is a standard idiom for branching on a boolean value. 1100 Node *c2b = cmp1; 1101 if( cmp2_type == TypeInt::ZERO && 1102 cmp1_op == Op_Conv2B && 1103 (_test._test == BoolTest::eq || 1104 _test._test == BoolTest::ne) ) { 1105 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int() 1106 ? (Node*)new (phase->C, 3) CmpINode(c2b->in(1),cmp2) 1107 : (Node*)new (phase->C, 3) CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR)) 1108 ); 1109 return new (phase->C, 2) BoolNode( ncmp, _test._test ); 1110 } 1111 1112 // Comparing a SubI against a zero is equal to comparing the SubI 1113 // arguments directly. This only works for eq and ne comparisons 1114 // due to possible integer overflow. 1115 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1116 (cop == Op_CmpI) && 1117 (cmp1->Opcode() == Op_SubI) && 1118 ( cmp2_type == TypeInt::ZERO ) ) { 1119 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(1),cmp1->in(2))); 1120 return new (phase->C, 2) BoolNode( ncmp, _test._test ); 1121 } 1122 1123 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the 1124 // most general case because negating 0x80000000 does nothing. Needed for 1125 // the CmpF3/SubI/CmpI idiom. 1126 if( cop == Op_CmpI && 1127 cmp1->Opcode() == Op_SubI && 1128 cmp2_type == TypeInt::ZERO && 1129 phase->type( cmp1->in(1) ) == TypeInt::ZERO && 1130 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) { 1131 Node *ncmp = phase->transform( new (phase->C, 3) CmpINode(cmp1->in(2),cmp2)); 1132 return new (phase->C, 2) BoolNode( ncmp, _test.commute() ); 1133 } 1134 1135 // The transformation below is not valid for either signed or unsigned 1136 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE. 1137 // This transformation can be resurrected when we are able to 1138 // make inferences about the range of values being subtracted from 1139 // (or added to) relative to the wraparound point. 1140 // 1141 // // Remove +/-1's if possible. 1142 // // "X <= Y-1" becomes "X < Y" 1143 // // "X+1 <= Y" becomes "X < Y" 1144 // // "X < Y+1" becomes "X <= Y" 1145 // // "X-1 < Y" becomes "X <= Y" 1146 // // Do not this to compares off of the counted-loop-end. These guys are 1147 // // checking the trip counter and they want to use the post-incremented 1148 // // counter. If they use the PRE-incremented counter, then the counter has 1149 // // to be incremented in a private block on a loop backedge. 1150 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd ) 1151 // return NULL; 1152 // #ifndef PRODUCT 1153 // // Do not do this in a wash GVN pass during verification. 1154 // // Gets triggered by too many simple optimizations to be bothered with 1155 // // re-trying it again and again. 1156 // if( !phase->allow_progress() ) return NULL; 1157 // #endif 1158 // // Not valid for unsigned compare because of corner cases in involving zero. 1159 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an 1160 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but 1161 // // "0 <=u Y" is always true). 1162 // if( cmp->Opcode() == Op_CmpU ) return NULL; 1163 // int cmp2_op = cmp2->Opcode(); 1164 // if( _test._test == BoolTest::le ) { 1165 // if( cmp1_op == Op_AddI && 1166 // phase->type( cmp1->in(2) ) == TypeInt::ONE ) 1167 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt ); 1168 // else if( cmp2_op == Op_AddI && 1169 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 ) 1170 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt ); 1171 // } else if( _test._test == BoolTest::lt ) { 1172 // if( cmp1_op == Op_AddI && 1173 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 ) 1174 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le ); 1175 // else if( cmp2_op == Op_AddI && 1176 // phase->type( cmp2->in(2) ) == TypeInt::ONE ) 1177 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le ); 1178 // } 1179 1180 return NULL; 1181} 1182 1183//------------------------------Value------------------------------------------ 1184// Simplify a Bool (convert condition codes to boolean (1 or 0)) node, 1185// based on local information. If the input is constant, do it. 1186const Type *BoolNode::Value( PhaseTransform *phase ) const { 1187 return _test.cc2logical( phase->type( in(1) ) ); 1188} 1189 1190//------------------------------dump_spec-------------------------------------- 1191// Dump special per-node info 1192#ifndef PRODUCT 1193void BoolNode::dump_spec(outputStream *st) const { 1194 st->print("["); 1195 _test.dump_on(st); 1196 st->print("]"); 1197} 1198#endif 1199 1200//------------------------------is_counted_loop_exit_test-------------------------------------- 1201// Returns true if node is used by a counted loop node. 1202bool BoolNode::is_counted_loop_exit_test() { 1203 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) { 1204 Node* use = fast_out(i); 1205 if (use->is_CountedLoopEnd()) { 1206 return true; 1207 } 1208 } 1209 return false; 1210} 1211 1212//============================================================================= 1213//------------------------------NegNode---------------------------------------- 1214Node *NegFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1215 if( in(1)->Opcode() == Op_SubF ) 1216 return new (phase->C, 3) SubFNode( in(1)->in(2), in(1)->in(1) ); 1217 return NULL; 1218} 1219 1220Node *NegDNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1221 if( in(1)->Opcode() == Op_SubD ) 1222 return new (phase->C, 3) SubDNode( in(1)->in(2), in(1)->in(1) ); 1223 return NULL; 1224} 1225 1226 1227//============================================================================= 1228//------------------------------Value------------------------------------------ 1229// Compute sqrt 1230const Type *SqrtDNode::Value( PhaseTransform *phase ) const { 1231 const Type *t1 = phase->type( in(1) ); 1232 if( t1 == Type::TOP ) return Type::TOP; 1233 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1234 double d = t1->getd(); 1235 if( d < 0.0 ) return Type::DOUBLE; 1236 return TypeD::make( sqrt( d ) ); 1237} 1238 1239//============================================================================= 1240//------------------------------Value------------------------------------------ 1241// Compute cos 1242const Type *CosDNode::Value( PhaseTransform *phase ) const { 1243 const Type *t1 = phase->type( in(1) ); 1244 if( t1 == Type::TOP ) return Type::TOP; 1245 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1246 double d = t1->getd(); 1247 return TypeD::make( StubRoutines::intrinsic_cos( d ) ); 1248} 1249 1250//============================================================================= 1251//------------------------------Value------------------------------------------ 1252// Compute sin 1253const Type *SinDNode::Value( PhaseTransform *phase ) const { 1254 const Type *t1 = phase->type( in(1) ); 1255 if( t1 == Type::TOP ) return Type::TOP; 1256 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1257 double d = t1->getd(); 1258 return TypeD::make( StubRoutines::intrinsic_sin( d ) ); 1259} 1260 1261//============================================================================= 1262//------------------------------Value------------------------------------------ 1263// Compute tan 1264const Type *TanDNode::Value( PhaseTransform *phase ) const { 1265 const Type *t1 = phase->type( in(1) ); 1266 if( t1 == Type::TOP ) return Type::TOP; 1267 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1268 double d = t1->getd(); 1269 return TypeD::make( StubRoutines::intrinsic_tan( d ) ); 1270} 1271 1272//============================================================================= 1273//------------------------------Value------------------------------------------ 1274// Compute log 1275const Type *LogDNode::Value( PhaseTransform *phase ) const { 1276 const Type *t1 = phase->type( in(1) ); 1277 if( t1 == Type::TOP ) return Type::TOP; 1278 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1279 double d = t1->getd(); 1280 return TypeD::make( StubRoutines::intrinsic_log( d ) ); 1281} 1282 1283//============================================================================= 1284//------------------------------Value------------------------------------------ 1285// Compute log10 1286const Type *Log10DNode::Value( PhaseTransform *phase ) const { 1287 const Type *t1 = phase->type( in(1) ); 1288 if( t1 == Type::TOP ) return Type::TOP; 1289 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1290 double d = t1->getd(); 1291 return TypeD::make( StubRoutines::intrinsic_log10( d ) ); 1292} 1293 1294//============================================================================= 1295//------------------------------Value------------------------------------------ 1296// Compute exp 1297const Type *ExpDNode::Value( PhaseTransform *phase ) const { 1298 const Type *t1 = phase->type( in(1) ); 1299 if( t1 == Type::TOP ) return Type::TOP; 1300 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1301 double d = t1->getd(); 1302 return TypeD::make( StubRoutines::intrinsic_exp( d ) ); 1303} 1304 1305 1306//============================================================================= 1307//------------------------------Value------------------------------------------ 1308// Compute pow 1309const Type *PowDNode::Value( PhaseTransform *phase ) const { 1310 const Type *t1 = phase->type( in(1) ); 1311 if( t1 == Type::TOP ) return Type::TOP; 1312 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1313 const Type *t2 = phase->type( in(2) ); 1314 if( t2 == Type::TOP ) return Type::TOP; 1315 if( t2->base() != Type::DoubleCon ) return Type::DOUBLE; 1316 double d1 = t1->getd(); 1317 double d2 = t2->getd(); 1318 if( d1 < 0.0 ) return Type::DOUBLE; 1319 if( d2 < 0.0 ) return Type::DOUBLE; 1320 return TypeD::make( StubRoutines::intrinsic_pow( d1, d2 ) ); 1321} 1322